U.S. patent number 9,255,835 [Application Number 13/591,635] was granted by the patent office on 2016-02-09 for system for remote vibration detection on combustor basket and transition in gas turbines.
This patent grant is currently assigned to Siemens Energy, Inc.. The grantee listed for this patent is Joshua S. McConkey. Invention is credited to Joshua S. McConkey.
United States Patent |
9,255,835 |
McConkey |
February 9, 2016 |
System for remote vibration detection on combustor basket and
transition in gas turbines
Abstract
A gas turbine combustor vibration sensing system includes a
non-contact reflective optical vibration sensor adapted for
reflecting photons off of a component within the combustor with a
photon source and receiving reflected photons with a photon
detector. Exemplary combustor internal components include the
combustor basket or transition. A vibration analyzer is coupled to
the vibration sensor, for correlating photons received by the
detector with vibration characteristics of the component. Vibration
characteristics in turn can be correlated with combustion
characteristics, including by way of example flame front position
and flameout conditions. Vibration characteristic information may
be used as an operational parameter by a turbine monitoring system
to modify operation of a gas turbine.
Inventors: |
McConkey; Joshua S. (Orlando,
FL) |
Applicant: |
Name |
City |
State |
Country |
Type |
McConkey; Joshua S. |
Orlando |
FL |
US |
|
|
Assignee: |
Siemens Energy, Inc. (Orlando,
FL)
|
Family
ID: |
48914473 |
Appl.
No.: |
13/591,635 |
Filed: |
August 22, 2012 |
Prior Publication Data
|
|
|
|
Document
Identifier |
Publication Date |
|
US 20140053574 A1 |
Feb 27, 2014 |
|
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
F23N
5/082 (20130101); G01H 9/00 (20130101); F23R
2900/00013 (20130101) |
Current International
Class: |
G01H
9/00 (20060101); F23N 5/08 (20060101) |
Field of
Search: |
;73/590,655,657,660
;60/773,39.281 |
References Cited
[Referenced By]
U.S. Patent Documents
Other References
Nicola Paone, et al. "Laser Vibration Measurements Through
Combustive Flows: Application to an Industrial Burner in Working
Conditions". In Measurements, vol. 28, No. 1, Jul. 1, 2000 (pp.
21-31). cited by applicant .
Artur Pozarlik. "Vibro-Acoustical Instabilities Induced by
Combustion Dynamics in Gas Turnbine Combustors". Dec. 3, 2010,
University of Twente, Enschede, NL (33 Pages). cited by
applicant.
|
Primary Examiner: Martin; Laura
Assistant Examiner: Miller; Rose M
Claims
What is claimed is:
1. A method for sensing combustion-induced vibration
characteristics in a gas turbine engine combustor, comprising:
providing an operating gas turbine engine, which includes a
combustor having a combustor housing, which defines an interior
including therein combustor basket and transition components that
entrain combustion gasses, and an inspection port in communication
with the housing interior that is accessible from outside the
housing, the inspection port including therein at least one optical
pipe or optical window for preventing combustion gas escape from
the housing interior; providing a non-contact reflective optical
vibration sensor in optical communication with the respective
inspection port optical pipe or window and the respective combustor
basket or transition components, the sensor having a photon source
and photon detector oriented outside the combustor housing;
providing a vibration analyzer coupled to the non-contact
reflective optical vibration sensor that correlates photons
received by the photon detector with vibration frequency and/or
magnitude characteristics; providing a gas turbine engine
monitoring system, coupled to the vibration analyzer, the
monitoring system capable of associating vibration characteristics
sensed by the sensor with operating engine vibration
characteristics that are indicative of combustion gas flame front
position or a flameout condition; reflecting photons off of an
exterior circumferential surface of the combustor basket or the
transition component within the operating combustor with the photon
source; receiving reflected photons with the photon detector
correlating, with the vibration analyzer and the monitoring system,
photons received by the detector with vibration characteristics of
the corresponding combustor basket or transition component and
identifying operating engine combustion gas flame front position or
a flameout condition therewith.
2. The method of claim 1, comprising using component vibration
characteristics as an operational parameter for operating the gas
turbine.
3. The method of claim 1, the vibration sensor comprising a laser
intensity sensor.
4. The method of claim 1, the vibration sensor comprising a laser
interferometry sensor.
5. The method of claim 1, the vibration sensor comprising a laser
Doppler sensor.
6. The system method of claim 1, the vibration sensor further
comprising at least one fiber optic cable inserted within the
inspection port, coupled to the photon source.
7. The method of claim 1, the vibration sensor further comprising
at least one fiber optic cable inserted within the inspection port,
coupled to the detector.
8. The method of claim 1, the vibration sensor further comprising
an optical tube and optical window inserted within the inspection
port.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to vibration detection in gas combustion
turbine combustors and more particularly to a system for remote
vibration detection on the combustor basket and/or transition in
gas turbines during their operation. Vibration is detected with one
or more non-contact reflective optical vibration (NROV) sensors
that are positioned within the combustor housing and reflect
photons off the combustor basket and/or transition combustion
containment components that are also within the housing. The sensed
vibration characteristics can be associated with combustion flame
characteristics, and used as a turbine operation monitoring
parameter.
2. Description of the Prior Art
Monitoring of steady state and transient vibration characteristics
within a gas turbine combustor section, and especially the
combustor basket and transition combustion containment components
are desirable tools for turbine design and operation. Those
components are susceptible to induced vibration excitation caused
by combustion gas dynamics A multitude of factors and operating
conditions provide for efficient and clean combustion dynamics
within the gas turbine combustor section during ongoing operation.
Although a stable lean mixture is desired for fuel efficiency and
for environmentally acceptable emissions, unstable engine operating
conditions must be avoided. Not only is the fuel/air mixture
important: also relevant to gas turbine operation are the shape and
location of the combustion flame front within the combustion
containment components, including the combustor basket and
transition. Given the efficiency and emissions criteria, the
operation of gas turbines requires a balancing of design and
operational approaches to maintain efficiency, meet emission
standards, and avoid vibrational, excessive pressure and/or thermal
damage due to undesired combustion dynamics characteristics.
Thus during gas turbine engine design and subsequent field
operation it is beneficial to monitor combustion vibration
characteristics that are impacted by combustion characteristics
such as: flame shape and flame front position; pressure variations;
thermoacoustic vibrations induced by combustion temperature and/or
pressure variations that may damage combustor components; flashback
and/or combustion flameout within one or more of the engine's
combustors. The monitored vibration and combustion characteristics
are then used as a control parameter for engine operation. For
example, if a combustor flameout is detected, a typical control
response is to shut fuel supply to at least the affected combustor,
if not the entire engine. In another example, if a flashback
condition is detected, a typical control response is to increase
air intake pressure and/or flow rate into the combustor.
Vibration and combustion characteristic direct monitoring with
instruments is difficult given the local pressure and temperature
conditions within a combustor, and particularly within the
combustor basket and transition combustion containment components.
Known combustion characteristic monitoring instrumentation include
single thermocouple or thermocouple arrays oriented within the
combustor, that associate temperature and/or changes in temperature
with combustion characteristics. However, temperature information
alone does not provide information about combustor vibration
characteristics. Other known combustion characteristic monitoring
instrumentation include one or pressure transducers (such as
piezo-electric transducer) oriented within the combustor, that
associate pressure and/or changes in pressure with combustion
characteristics. Pressure transducers can also monitor
thermoacoustic vibrations induced by combustion temperature and/or
pressure variations that may damage combustor components, so that
useful vibration monitoring information is available for turbine
design and operation. Some proposed known combustion monitoring
optical systems associate flame luminescence with combustion
thermoacoustic vibration characteristics, eliminating the need for
a pressure transducer to perform the same vibration monitoring
function. These optical sensors measure changes in combustion flame
luminescence (e.g., in any of the infra-red, visible light or
ultraviolet spectra) and may include optical pipes inserted within
the combustor that are coupled to photodiode detectors located
outside or inside the combustor housing. Combustion monitoring by
laser-optical sensors employing backscatter, diffraction or
phase-Doppler principles have been proposed for monitoring cooling
water injection content and droplet distribution within the
combustor, but they do not provide vibration monitoring
information.
Other known combustor vibration monitoring systems utilize
accelerometers that can also associate sensed vibration
characteristics with combustion characteristics. The accelerometers
can be mounted inside or outside the combustor housing.
Accelerometers, or for that matter any type of monitoring sensor
that is mounted within the combustor, are susceptible to damage
from hot pressurized combustion gasses, reducing their potential
service reliability. Failed combustion monitoring sensors mounted
within combustors require engine shutdown--hence service
interruption--to facilitate their replacement. If the accelerometer
or other vibration sensor is mounted to internal combustor
components, full combustor tear-down may be required to replace
them. If accelerometers or any other vibration measuring sensors
are affixed to a combustion containment component, such as a
combustor basket or transition, they may also negatively impact
vibration characteristics of the component itself--for example by
introduction of unbalanced undamped mass. Additionally, if an
accelerometer or other vibration measuring sensor inadvertently
separates from an attachment point within the combustor it may
cause internal damage to other components. While accelerometers or
other combustion/vibration monitoring sensors may also be mounted
external the combustor housing, avoiding all of the above-noted
disadvantages, they may not offer the same monitoring sensitivity
and/or response rate as those mounted within the combustor housing
due to, among other things, housing vibration attenuation or
propagation delay.
Thus, a need exists in the art for a gas turbine combustor
vibration monitoring system that functions reliably despite high
temperature and pressure conditions within an operating
combustor.
Another need exists in the art for a gas turbine combustor
vibration monitoring system that provides high monitoring
sensitivity and response, without adversely impacting vibrational
characteristics of combustor internal components.
An additional need exists in the art for a gas turbine combustor
vibration monitoring system facilitates association of sensed
vibration characteristics with combustion characteristics, and the
characteristic information used as an operating parameter by the
turbine monitoring system to modify operation of the gas
turbine.
SUMMARY OF THE INVENTION
Accordingly, an object of the invention is to monitor combustion
characteristics within a gas turbine combustor in a reliable
manner, despite high temperature and pressure conditions within an
operating combustor.
Another object of the invention is to monitor gas turbine combustor
vibration with high monitoring sensitivity and response, without
adversely impacting vibration characteristics of combustor internal
components.
An additional object of the invention is to facilitate association
of sensed vibration characteristics with combustion
characteristics, and the characteristic information used as an
operating parameter by the turbine monitoring system to modify
operation of the gas turbine.
These and other objects are achieved in accordance with the present
invention by embodiments of the gas turbine combustor vibration
sensing system that include a non-contact reflective optical
vibration sensor adapted for reflecting photons off of a component
within the combustor with a photon source and receiving reflected
photons with a photon detector. Exemplary combustor internal
components include the combustor basket or transition. The
non-contact optical sensor does not influence vibration
characteristics of the combustor internal component, and can be
replaced without full combustor tear-down by removal and
replacement through a housing inspection port. The non-contact
optical sensor is spaced from the combustor internal component and
thus operates at a lower temperature than the internal component. A
vibration analyzer is coupled to the non-contact vibration sensor,
for correlating photons received by the detector with vibration
characteristics of the component. Vibration characteristics in turn
can be correlated with combustion characteristics, including by way
of example flame front position and flameout conditions. Vibration
characteristic information may be used as an operational parameter
by a turbine monitoring system to modify operation of a gas
turbine.
Embodiments of the present invention feature a method for sensing
vibration in a gas turbine combustor, by reflecting photons off of
a component within the combustor with a photon source of a
non-contact reflective optical vibration sensor and receiving
reflected photons with a photon detector of the vibration sensor. A
vibration analyzer is used to correlate photons received by the
detector with vibration characteristics of the component.
Other embodiments of the present invention feature a gas turbine
combustor vibration sensing system having a non-contact reflective
optical vibration sensor adapted for reflecting photons off of a
component within the combustor with a photon source and receiving
reflected photons with a photon detector. A vibration analyzer is
coupled to the vibration sensor, for correlating photons received
by the detector with vibration characteristics of the
component.
Additional embodiments of the present invention feature a gas
turbine system having a combustor, with a combustor housing
including combustor basket and transition components. A combustor
vibration sensing system is coupled to the combustor, having a
non-contact reflective optical vibration sensor in communication
with an interior of the combustor housing. The vibration sensor
reflects photons off of at least one of the components with a
photon source and receives reflected photons with a photon
detector. A vibration analyzer is coupled to the vibration sensor,
for correlating photons received by the detector with vibration
characteristics of the component.
The objects and features of the present invention may be applied
jointly or severally in any combination or sub-combination by those
skilled in the art.
BRIEF DESCRIPTION OF THE DRAWINGS
The teachings of the present invention can be readily understood by
considering the following detailed description in conjunction with
the accompanying drawings, in which:
FIG. 1 is a schematic, partial cross-sectional elevational view of
a gas turbine including an exemplary embodiment of the vibration
sensing system of the present invention; and
FIG. 2 is a block diagram of an exemplary embodiment of the
vibration sensing system of the present invention.
To facilitate understanding, identical reference numerals have been
used, where possible, to designate identical elements that are
common to the figures.
DETAILED DESCRIPTION
After considering the following description, those skilled in the
art will clearly realize that the teachings of the present
invention can be readily utilized in a gas turbine combustor
vibration sensing system, which includes a non-contact reflective
optical vibration sensor adapted for reflecting photons off of a
component within the combustor with a photon source and receiving
reflected photons with a photon detector. Exemplary combustor
internal components suitable for vibration monitoring include the
combustor basket or transition. The non-contact sensor does not
have to be mounted within the combustor casing so long as the
transmitter and receiver have optical line of sight alignment with
the combustor basket or transition. Thus it does not impact
inherent vibration characteristics of the combustor internal
components, is easily installed, replaced or reconfigured in the
field via a combustor housing inspection port, and cannot break
loose from an internal mounting position where it might cause
internal damage to the combustor. A vibration analyzer is coupled
to the vibration sensor, for correlating photons received by the
detector with vibration frequency and/or magnitude characteristics
of the component. Vibration characteristics in turn can be
correlated with combustion characteristics, including by way of
example flame front position and flameout conditions. Vibration
characteristic information may be used as an operational parameter
by a turbine monitoring system to modify operation of a gas
turbine.
FIG. 1 shows an exemplary combustion gas turbine 10 of known
construction, having a compressor section 12, a combustor section
14 and a turbine section 18, through all of which is oriented rotor
18. The combustor section 14 includes a combustor housing 20 that
contains the high temperature pressurized combustion gases, which
impart rotation on turbine blades within the turbine section 16.
Generally a gas turbine combustion section 14 has a plurality of
circumferentially oriented combustors, and only one exemplary
combustor is shown in FIG. 1. Combustion containment component
section 30 includes combustor basket 32 and transition 34 that
isolate the combustion flame front F within the combustor section
14. The flame front F pulsates and varies position dynamically
within the combustor containment component section 30. The flame
front F pulsation position and intensity vibrate the combustion
containment component section 30, including the combustor basket 32
and transition 34. Their vibration characteristics are correlated
with combustion characteristics, for example flame front positions
or a flameout condition.
In the exemplary embodiment of FIGS. 1 and 2 the vibration sensing
system of the present invention includes two non-contact reflective
optical vibration (NROV) sensors 40, 50 in communication with the
combustor housing interior. While two NROV sensors are shown, a
single sensor or more than two sensors may be utilized in an
individual combustor. Similarly, each individual combustor in the
combustor section 14 may utilize one or more NROV sensors. As shown
in FIGS. 1 and 2 the respective NROV sensors 40, 50 reflect
reflecting photons off of at least one of the combustion
containment components 30 with a photon source (often a coherent
photonic beam laser source) along a path I and receiving reflected
photons with a photon detector (e.g., a solid-state charged coupled
device) along the path R. The NROV sensors 40, 50 are of known
construction and can utilize laser intensity, laser interferometry
or laser Doppler sensing principles that correlate relative
position of the sensor and the reflective surface.
Operation and function of an exemplary NROV sensor adapted for
electrical generator vibration monitoring is shown and described in
U.S. Pat. No. 7,533,572 "High Bandwidth Fiber Optic Vibration
Sensor", the entire contents of which is incorporated herein by
reference. Changes in vibrational relative position frequency and
amplitude can be monitored by vibration analyzer 60.
Exemplary NROV sensors 40 and 50 are inserted in inspection ports
22, 24 formed within the housing, so that their respective sources
and detectors are in optical line of sight with exterior surfaces
of the respective paired transition 34 and combustor basket 32.
Sensor 40 includes fiber optic pipe assemblies 42, 44 of known
construction, which are coupled respectively to its source and
detector. Both of the fiber optic pipes 42, 44 are capable of
operating within the relatively harsh temperature and pressure
conditions of the combustor section 14 interior, so that the
remainder of the sensor 40 source and detector components remain
outside the gas turbine. The sensor 50 has an optical tube 52 with
a high temperature resistant optical window 54 that is inserted
into the inspection port 22 and in communication with the combustor
section 14 interior. In this way the remainder of sensor 50
components remains outside the gas turbine. While the exemplary
embodiment of FIG. 1 has a single sensor in each of inspection
ports 22, 24, more than one sensor may be inserted in one access
port, and each of the multiple sensors can be oriented to project
and receive reflected photons from different combustor components
(e.g., the combustor basket 32 and the transition 34, or different
portions of one component (e.g., the upstream and downstream end of
the combustor basket 32). By way of example, multiple sensors can
be accommodated in a single inspection port 22, 24 by inserting and
separately orienting a plurality of fiber optic pipes 42, 44 for
different sensors therein or by adding an optical prism in series
with the optical window 54 within the optical tube 52.
NROV sensors 40, 50 are coupled to a known vibration analyzer 60
that controls each sensor and converts sensor detector readings to
sensed vibration frequency and/or magnitude characteristics. The
vibration analyzer 60 includes a controller 62 and operating
implementing software and/or firmware instruction sets stored in
accessible memory 64 for implementing the detector reading to
vibration characteristic association. Combustor basket 32 and/or
transition 34 vibration characteristics are communicated by
vibration analyzer 60 to a gas turbine monitoring system 70 by
communication pathway 72. The gas turbine monitoring system 70 can
associate the vibration characteristic information with turbine
operating conditions and use that information as a control or other
operational parameter for running the gas turbine 10. For example
if the gas turbine monitoring system 70 associates a vibrational
characteristic with a flameout condition, it can cause the
combustor fuel injector to cease supplying fuel to the combustor
section 14. The gas turbine monitoring system 70 communicates via
communication pathway 74 to a power plant control system
communication bus 80, where operating conditions including by way
of example vibration characteristics sensed by the NROV sensors 40,
50, can be monitored by plant operators via human machine interface
(HMI) 90. Thus human operators can also utilize monitored
vibrational characteristic information when operating the power
plant.
Although various embodiments that incorporate the teachings of the
present invention have been shown and described in detail herein,
those skilled in the art can readily devise many other varied
embodiments that still incorporate these teachings. The invention
is not limited in its application to the exemplary embodiment
details of construction and the arrangement of components set forth
in the description or illustrated in the drawings. The invention is
capable of other embodiments and of being practiced or of being
carried out in various ways. Also, it is to be understood that the
phraseology and terminology used herein is for the purpose of
description and should not be regarded as limiting. The use of
"including," "comprising," or "having" and variations thereof
herein is meant to encompass the items listed thereafter and
equivalents thereof as well as additional items. Unless specified
or limited otherwise, the terms "mounted," "connected,"
"supported," and "coupled" and variations thereof are used broadly
and encompass direct and indirect mountings, connections, supports,
and couplings. Further, "connected" and "coupled" are not
restricted to physical or mechanical connections or couplings.
* * * * *